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    Relational Database: It is a type of database that stores data
                        in several tables and links those tables together through keys
                        that  allows  efficient  data  retrieval  and  reduced  redundancy.
                        Commonly  used  relational  database  systems  are  LibreOffice
                                                                                           Microsoft Access LibreOffice Base
                        Base, Microsoft Access, etc.
                     Clickipedia

                       The  relational  database was  proposed  by  Edgar F.  Codd.  He  gave  a  set  of  thirteen  rules
                       (Codd’s rules) to define a Relational Database Management System.

                           ADVANTAGES OF A DATABASE SYSTEM

                     A database system has many advantages. Some of the important advantages are:
                        It minimises the redundancy of data by organising data in a structured manner. This ensures
                        that data is not unnecessarily repeated across tables.

                        It saves the storage space.
                        All the users are provided with some access rights or privileges and permissions.
                        The files can be easily updated whenever changes are being made.

                           DATABASE OBJECTS

                     Data in a database is organised into tables. A table is the building block of a database. A single
                     database file can contain one or more tables. It contains data in the form of rows and columns
                     and looks similar to a spreadsheet. A column in a table is called a field. A row in a table is called
                     a record. A row contains a single entry for each column.

                                                                       FIELDS

                                  Reg No.          Name            Father’s Name       Date of Birth       Class

                                  187/11     Aashi Kant          Mr. P.S. Kant        15/08/2007            VIII
                             RECORDS  156/12  Nazia Sharma       Mr. R.K. Sharma      22/10/2008             IX

                                  194/11
                                             Rajesh Patel
                                                                                      16/04/2008
                                                                                                             IX
                                                                 Mr. V.S. Patel
                                  123/12     Niraj Sagar         Mr. A.K. Sagar       18/06/2007            VIII
                     The commonly used terms of the relational database are:

                        Table: It is a group of related data organised in columns and rows in a database. The columns
                        contain a number of headings such as Reg No., Name, Father's Name, Date of Birth, Class, etc.
                        These are known as fields. A set of values for the fields is called a Record. Each row in the
                        table represents one record.
                        Primary Key: It is a unique field by which the records are uniquely identified in a table.
                        A table can have only one primary key. It ensures that no two records have the same value for
                        this field. For example, in a student’s record the ‘Reg No.’ can be called a primary key.

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